Mixing hypodermic syringe

US6817987B2 · kind B2 · utility

Assignee

• ARZNEIMITTEL GMBH APOTHEKER VETTER & CO. RAVENSBURG · DE

Inventors

• Udo J. Vetter · Ravensburg, DE
• Thomas Otto · Würzburg, DE

Key dates

• Filing date: Aug 16, 2002
• Grant date: Nov 16, 2004
• Expiry date: Aug 16, 2022

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61M2005/31508
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

A syringe holding a solvent and a soluble component has a tubular body formed its front and rear ends with a bypass, a plunger axially slidable in the body, and a stem projecting axially rearward out of the body from the plunger. A cover fits over the front end of the body and is so tight that the front compartment can be pressurized to a superatmospheric pressure without leakage out the front end. A free piston slidable in the body forward of the plunger subdivides the body forward of the plunger into a front compartment at the front body end holding the soluble component and a rear compartment between the plunger and the piston and holding the solvent. Stops are provided for arresting the free piston when it is level with the bypass in a position permitting flow through the bypass between the compartments.